As a man gets older testosterone is converted into di-hydrotestosterone (DHT), which some believe is the cause of benign prostatic hyperplasia (BPH) and cancer, but some do not.
Estrogen levels also increase as a man gets older. Estrogen is known to stimulate cell growth. Reading between the lines, because as yet, there is no definitive study done on this, it appears to be the increased estrogen level which is the problem and not the two testosterones. As progesterone is a powerful counter-balance for estrogen, progesterone for men is essential.
If in fact testosterone were the culprit, then men aged ±22 would have the highest incidence of BPH and cancer, as testosterone levels are at their highest point in the early 20's, but of course they don't. From the early twenty's to the late twenty's testosterone makes it's greatest drop, thereafter it continues to decline, but at a slower rate.
BPH starts affecting a man in his fifties and interestingly Estradiol levels start climbing from the age of fifty and are at their highest point in men in their late 60's, but during the same period progesterone levels are declining. Progesterone for men becomes that much more important with age.
5-alpha reductase inhibitors such as finasteride are usually given to prevent the conversion of testosterone to DHT, but research has found that progesterone is a natural inhibitor of 5-alpha reductase.
Progesterone also down regulates the action of oestrogen if used in a sufficiently high dose. The endogenous oestrogen made by humans is now being supplemented by synthetic oestrogens found in the environment. They are now found in food, air, water, plastics, skin care products, no one can avoid them. Some authorities speculate this is the cause of the increase in problems such as hyperplasia or cancers of any hormonally sensitive tissues, such as the prostate, endometrium, cervix and breasts. So, despite often being, erroneously, thought of as a 'female' hormone progesterone for men is essential to preserve masculinity!
Below are the reference ranges for Estradiol testosterone and progesterone for men...
Estradiol 0.5 - 2.2 pg/ml
Progesterone 15 - 100 pg/ml
Testosterone 44 - 148 pg/ml
As a reference point, the same hormones below are for women.
Estradiol 1.3 - 3.3 pg/ml
Progesterone 75 - 270 pg/ml
Estradiol 0.5 - 1.7 pg/ml
Progesterone 12 - 100 pg/ml
Range for all ages
Testosterone 16 - 55 pg/ml
Salivary hormone levels are often higher than serum (blood) levels when hormones are delivered topically (on the skin).
One of the most perplexing issues surrounding saliva testing is the odd phenomenon that topically delivered steroids cause a dramatic increase in salivary hormones without a concomitant increase in serum levels. For example, 30 mg topical progesterone supplementation results in an average rise in salivary levels from about 50 pg/ml (0.05 ng/ml) to 500 to 3000 pg/ml (0.5 to 3 ng/ml), a 10 to 60-fold increase.
This increase is proportionally even greater when progesterone is supplemented at 100 to 200 mg, a common topical dose used by many doctors, resulting in salivary progesterone levels rising to as high as 10,000 to 100,000 pg/ml (10-100 ng/ml). Under the same conditions, serum progesterone levels only increase about 4-fold, from about 0.5 to 2-3 ng/ml. The same disproportionate increase in salivary hormone levels is seen with topical delivery of all the other steroid hormones (eg. Estradiol, testosterone, DHEA. Etc.